JPS6157499B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in the sliding part sealing structure of a pin type disc brake.

In general, in pin type disc brakes, in order to ensure long-term slidability of the caliper in the disk axial direction, there is an opening formed in one of the supports or the caliper, and a pin type disc brake that is fixed to the other side of the support or caliper and connected to the opening. It is desirable that the sliding portion of the caliper with the slide pin, which guides the sliding movement of the caliper in the disk axial direction by forming a sliding relationship, be shielded from the outside air by an elastic boot or the like. The purpose of sealing the sliding parts is to prevent rainwater or moisture from entering from the outside, causing rust on the sliding parts and causing poor sliding. Even if there is an increase in air pressure due to a change in the volume inside the stop, it cannot be released to the outside, and this air pressure may cause the caliper to slide when the brake is not on, causing a dragging problem, or cause the elastic boot to slide. There was a risk that the sealing portion would become disengaged due to the large amount of water.

The present invention was made in order to eliminate such problems, and one end of the elastic boot is opened to the outside of a diameter formed in one opening of the caliper or the support, or the outer periphery of the slide pin fixed to the other. The elastic boot is tightly engaged with the circumferential groove, and normally this tight engagement shuts off the outside air and the inside of the seal, and when the air pressure inside the seal increases, one end of the elastic boot deforms or tilts, causing the end of the elastic boot to deform or tilt. This is a sliding part sealing structure for a pin type disc brake, characterized in that it is configured to open a normally-closed communication passage formed in the vicinity of the sealing part and the outside air to communicate with the inside of the seal.

The present invention will be described below based on embodiments shown in the drawings.

Embodiment 1 In FIGS. 1 and 2, 1 is a slide pin, which is fixed to a caliper (not shown) and is assembled into an opening 3 formed in a support 2 so as to form a sliding relationship. There is. 4 is a circumferential groove formed at the edge of the opening 3 of the support 2 so as to open radially outward; 5 is a circumferential groove formed to be located outside the opening 3 of the slide pin 1; 6 is a circumferential groove between these two circumferential grooves. It is an elastic boot that covers the sliding part and insulates it from the outside air by being constructed over the parts 4 and 5, and the enlarged part 7 at one end extending from the meandering abdomen in a double cylindrical shape is attached to the one end. The enlarged portion 8 at the other end is similarly tightly engaged with the other circumferential groove 5 by elastic force.

The abdomen in the vicinity of the enlarged end portion 7 is normally tightly connected to the outer periphery of the support 2, and when the tightened connection is released, it forms a normally closed connection that communicates the sealed interior 10 with the outside air. aisle 9
is provided.

According to this configuration, when the slide pin 1 and the support 2 move relative to each other in the axial direction during brake assembly, etc., and the volume of the sealing interior 10 decreases, the air pressure in the sealing interior 10 decreases due to the volume reduction. The abdomen near the bulge at one end of the elastic boot 6, which normally closes the communication path 9 by tightly engaging the outer periphery of the support 2, bulges outward and rises as shown in FIG. The air pressure in the sealed interior 10 can be released to the outside air through the communication path 9, and when the air pressure in the sealed interior 10 is balanced with the outside air, the communication path 9 is closed again and the sealed state is maintained.

Embodiment 2 In this embodiment, as shown in FIGS. 3 to 5, the enlarged portion 7' at one end, which is tightly engaged with the circumferential groove 4 of the support 2' of the elastic boot 6', is loosely fitted into the circumferential groove 4'. A communicating passage 9' consisting of a radial notch is provided at the edge thereof, and the air pressure is released to the outside air by tilting the sealed interior 10' of the enlarged portion 7 as the air pressure increases. The other configurations are the same as in the first embodiment.

Embodiment 3 In this example, as shown in FIGS. 6 and 7, the enlarged portion 8'' at the other end of the elastic boot 6'' is loosely fitted into the circumferential groove 5'' of the slide pin 1'', and the sealing interior 10'' is closed. The structure is such that air pressure is released to the outside air through a communication path 9'' formed in the slide pin 1'' by tilting of the enlarged portion 8'' as the air pressure increases, and the structure is different from the above embodiments 1 and 2. Although different, similar effects can be obtained.

As described above, the sliding part sealing structure of the pin type disc brake according to the present invention sufficiently prevents the intrusion of rainwater, etc., which is the main purpose of the sealing, but on the other hand, the air pressure inside the sealing It is also possible to prevent an increase in the amount of water, and the practical benefits thereof are extremely large.

[Brief explanation of the drawing]

The drawings all show embodiments of the present invention, and FIG. 1 is a partial sectional view showing the sliding part of Embodiment 1, FIG. 2 is an explanatory diagram when air pressure in the same part is released to the outside air, and FIG. The figure is a partial sectional view showing the sliding part of the second embodiment, and the fourth
The figure is a plan view of the same part, Figure 5 is an explanatory diagram when air pressure in the same part is released to the outside air, Figure 6 is a partial sectional view showing the sliding part of Example 3, and Figure 7 is the same part. It is an explanatory view when air pressure is released to outside air. 1, 1', 1''...Slide pin, 2, 2',
2″...Support, 3,3′...Opening, 4,4′...
Circumferential groove, 5,5''...circumferential groove, 6,6',6''...elastic boot, 7,7'...ampulla, 8,8''...ampulla,
9, 9', 9''...Communication path, 10, 10', 10''...
...Inside the seal.

Claims (1)

[Claims] 1 Press one side of the opposing friction pad against the disc,
A caliper that slides in the disk axial direction due to this reaction force and presses the other friction pad against the disk, a fixed support provided at the edge of the disk, and a caliper fixed to one of these calipers or supports. and a slide pin that is in a sliding relationship with an opening formed in the other side of the caliper or the support so that it can slide in the disk axial direction, and elasticity that covers the edges of these openings and the outer periphery of the slide pin to isolate the sliding part from the outside air. In a pin type disc brake equipped with a sealing structure consisting of a boot, the sealing structure is such that at least one end of the elastic boot is in contact with the opening edge or a circumferential groove opened radially outward formed on the slide pin. The boot is configured to be connected and deformed or tilted by an increase in air pressure inside the seal, and at or near one end of the boot, there is a connection between the outside air and the inside of the seal, which is opened only when the one end is deformed or tilted. A sliding part sealing structure for a pin type disc brake characterized by having a communication path.